> It is Chapter 3 which contains the normative definition of conformance
> to the standard.

Here's John's Own Version Of Unicode Compliance:

1) Unicode characters are 16 bits long; deal with it.
2) Byte order is only an issue in files.
3) If you don't have a clue, assume big-endian.
4) Loose surrogates don't mean jack.
5) Neither do U+FFFE and U+FFFF (a.k.a. the zigamorph).
6) Leave the unassigned codepoints alone.
7) It's OK to be ignorant about a character, but not plain wrong.
8) Subsets are strictly up to you.
9) Canonical equivalence matters.
10) Don't garble what you don't understand.

This is presented in the hope that it may be useful, but all
warranties (including implicit warranties of merchantability or
fitness for a particular purpose) are void. Freely reusable,
except that John Cowan asserts the moral right to be known as author.